That seems like a strange question to ask and a hard one to argue. If you'll grant that incest is immoral, many consider first cousins too close to have sex with. Leviticus does not expressly forbid sex with cousins, though it does say no sex with "close relatives" ; I don't know about other religions. But, it is not uncommon in this country to consider sex between first cousins to be incestuous. How often do people give a little gross-out face when they hear about Hitler marrying his cousin, or Frankenstein his, etc.
Yeah, I admit it is strange to ask but the topic is about legalizing a Western social taboo. The idea of marrying my first cousin does gross me out a little, but the practice isn't uncommon outside of the West, and the article does give examples of people who did marry their first cousins. And just because it grosses me out doesn't mean it's immoral.
